Best-selling author A.J. Jacobs is no stranger to big projects. After reading the entire Encyclopedia Brittanica for his book The Know-It-All,Jacobs spent a year trying to follow the Bible as literally as possible for his 2007 book, The Year of Living Biblically. For his most recent release Thanks A Thousand: A Gratitude Journey, Jacobs tracked down everyone involved in producing his morning cup of coffee– from the farmer to barista and everyone in between — just to say thank you. Jacobs was kind of enough to answer our questions about the book, and, of course, let of know what coffee he’s drinking these days.

First of all, congratulations on your new book. Where did the inspiration to Thanks a Thousand come from?

It started a couple of years ago. I’d read about all the many health benefits of gratitude – both mental and physical health – so I decided to say a prayer of thanksgiving before meals. But I’m not religious. So instead of thanking God, I would thanks some of the people involved in my meal. I’d say, “I’d like to thank the tomato farmer, and the cashier at the grocery store who sold me the tomato.” And one day, my 10-year-old son said, “You know, dad, those people can’t hear you. If you really cared, you’d go thank them in person.” And I thought, that’s a great idea. That would make a lovely book. So that sparked the journey.

And I decided to focus on coffee instead of my whole meal. This is because, first, I love coffee. I see it as one of Maslow’s hierarchy of needs, right up there with food and shelter. Second, it’s so ubiquitous – 2 billion cups are drunk every day, 125 million people have jobs related to the coffee trade. And what a history! The Enlightenment was started in coffee houses.

I was one of those kids who was forced to write a thank you note for every birthday or Christmas present, no matter how minuscule, but I confess I haven’t continued that tradition as an adult. Do you think we’ve forgotten how to be grateful as a society?

I do think it’d help the world if we embraced gratitude more. I know it’s kind of a pain to write notes, but if you can spare the two minutes, it actually makes both people feel better – the thanker and the thankee. As Benedictine monk David Steindl-Rast says, “Happiness does not lead to gratitude. Gratitude leads to happiness.”

The coffee industry has been pushing transparency and traceability from seed to cup for a while. You took that one step further, even meeting the steel workers who helped make your coffee machine. What was the most illuminating part of your journey?

I was amazed by the hundreds of people it takes to make my morning cup of coffee. I knew about the farmer and the barista, but I loved meeting the roasters, the logo designer, the guy who built the palette that carries my coffee beans on the ship. And, as the designer of my coffee cup lid said, “Coffee is very delicate. Tweak just a few things in coffee and it becomes cat piss.” So every step along the way requires thought and care. Even the lid—he said a bad lid can ruin a cup of coffee by blocking the aroma.

What were some of the reactions of the people you met? Were they thankful for the recognition?

Most of them, yes. I mean, there were a few people who were skeptical. I made hundreds of visits and calls and emails to folks along the chain. And some of them were like, “What’s going on here? Is this a pyramid scheme? What are you trying to sell?” But the majority were really happy to hear from me. I remember calling the woman who does pest control for the warehouse where my coffee is stored. And I said, “I know this sounds strange, but I just want to thank you for keeping the bugs out of my coffee.” She said, “That does sound strange. But thank YOU! We rarely get appreciated. You just made my day.” And that made my day. There was a recent study that said we overestimate how awkward it is to thank people, and we underestimate how meaningful it is to them.

What is your go-to cup of coffee? Do you have a favorite roaster or origin? Cream and sugar or just black?

There’s a coffee from Colombia called Geisha coffee, from the farm Manatiales del Frontino. Ed Kaufmann, the head of sourcing at Joe Coffee, calls it “Willy Wonka coffee,” because it’s like the Everlasting Gobstopper – just a series of waves of flavor after flavor. I’m not sophisticated enough to distinguish all the flavors, but I catch some of them. Plus I love Willy Wonka.

And I try to drink it black, because I know that’s what proper coffee people should do. But sometimes I’m weak and add almond milk. Sorry, Ed! Forgive me.

Photo by Lem Lattimer, courtesy of A.J. Jacobs.